(1) Field of the Invention
The present invention relates to a method for supplying a water-in-oil (hereinafter, abbreviated as W/O) emulsion explosive into a cartridge machine, and an apparatus used for the method; and more particularly relates to a method for supplying a W/O emulsion explosive into a cartridge machine, which method has made possible to pack even a W/O emulsion explosive having very low consistency by means of the cartridge machine, and an apparatus (hereinafter, referred to as "feeder") used for the method.
(2) Description of the Prior Art
There has heretofore been used a cartridge machine (for example, Rollex cartridge machine, made by Niepmann Jmbh & Co.) for gelatin dynamite in the packing of a W/O emulsion explosive in a paper tube.
However, W/O emulsion explosives capable of being packed by this cartridge machine are limited to ones having high consistency, and it is difficult to pack W/O emulsion explosive having low consistency due to the fact that explosives having low consistency to every portions in the cartridge machine due to their high adhesion.
The reason why such troubles occur is that the cartridge machine for gelatin dynamite is designed for packing rigid, plastic and non-adhesive gelatin dynamite.
A W/O emulsion explosive generally has a temperature higher than 80.degree. C. after kneading during the course of the production of the explosive due to the properties of the starting raw materials, and is generally soft and adhesive. Accordingly it is difficult to directly pack the soft and adhesive explosive by means of the above described cartridge machine unless the explosive is modified into a rigid, plastic and non-adhesive explosive. Therefore, the soft and adhesive explosive has heretofore been packed after the explosive had been modified into form by cooling.
However, this requires a cooling step to be used for the cooling of the W/O emulsion explosive. Further, natural cooling requires a long period of time (for example, several tens of hours) due to the poor heat transfer coefficient of the W/O emulsion explosive.
There has been proposed a method in Japanese Patent Laid-open Specification No. 34,095/82, wherein a specifically limited petroleum wax is used as a carbonaceous fuel constituting the continuous phase of a W/O emulsion explosive in order to improve the consistency of the explosive.
However, even in the above proposed method, it is necessary to cool the raw material mixture containing the petroleum wax to a temperature lower than the melting point of the petroleum wax, and moreover the kind and amount of the carbonaceous fuels to be used in the above proposed method must be selected from narrow ranges respectively due to the fact that petroleum wax is an essential ingredient as a carbonaceous fuel in the explosive.
Accordingly, there has been great demand to develop a method capable of packing a W/O emulsion explosive having a low consistency by means of a cartridge machine without the use of a cooling step and further without narrowly limiting the composition of the explosive.